Well up in colour (7)

I believe the answer is:

suffuse

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'well up in colour' is the definition.
The definition and answer can be both related to change as well as being verbs in their base form.
Maybe they are linked in a way I don't understand?

This is all the clue.

Can you help me to learn more?

(Other definitions for suffuse that I've seen before include "Of colour, spread slowly throughout" , "Spread; permeate" , "Flood through" .)

I've seen this clue in The Globe and Mail, The Telegraph and The Guardian.

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